What is a key characteristic of a corrugated container?

A key characteristic of a corrugated container is that it consists of a series of folds and ridges. This design feature not only contributes to its structural strength and durability but also allows for lightweight yet robust packaging solutions. The corrugations create air pockets that enhance the container's ability to withstand external pressure and impacts, making it ideal for shipping and storage.

The other options do not accurately represent the defining elements of corrugated containers. For instance, while high-density plastic may be used in some types of containers, it is not a characteristic of corrugated materials, which are primarily made from paper pulp. The design of corrugated containers is focused on short to medium-term use, rather than specifically long-term use, which is not characteristic of their intended function. Enhanced insulation properties pertain more to specific insulating materials rather than corrugated structures themselves, which are valued for their lightweight and protective qualities rather than thermal insulation.